Tasman secured promotion to the ITM Cup Premiership, claiming their first title in the most dramatic circumstances as Hawke's Bay five-eighth Ihaia West missed a last-minute sideline conversion to win the game.

Tasman went into the match firm favourites, having topped the round-robin ladder with a combination of the most prolific attack and the best defence in the Championship, but they won with a wonderful defensive effort. Hawke's Bay dominated possession and territory throughout, but the Makos held firm in defence often enough and long enough to secure the victory.

Alby Mathewson, in particular, sparked numerous big breaks on the short side for the Magpies, but they paid the price for mistakes at key times against resolute defence that forced turnovers. The Magpies also were undone by inaccurate goal-kicking from West, the young five-eighth who had kicked at 79% through the season, seemingly suffering nerves badly as he missed three penalties as well as the match-winning attempt at the death.

Hawke's Bay opened the scoring when Zac Guildford scored a try early in the first half the former All Blacks star touching down by the posts after relentless pressure. Bryce Heem crossed for the Makos within 10 minutes, powering through the Magpies defence as Tasman shifted the ball right, before West and Marty Banks, rising stars among the nation's young five-eighths, traded penalties.

Tasman turned the game on its head when they scored two tries withing four minutes in the final quarter of the period. Liam Squire ranged wide on the right flank to cross after the Makos had broken from defence only to be denied on the left by Karl Lowe, scoring his seventh try of the season, before Banks broke 90 metres after intercepting West's tap penalty with the Magpies hard on attack. It was to be a match-winning period.

Hawke's Bay dominated again in the second half, but again they struggled to breach the defence before finally crossing the stripe through Brendon O'Connor on the right after the Makos had somehow held them out on the left flank.

Banks kicked a long-range goal 10 minutes from full-time to give the Makos breathing space with a nine-point margin, but West, who had rediscovered his radar to convert O'Connor's try, replied almost immediately from distance to put the result back in doubt.

The Magpies went back on the attack in the final five minutes, developing relentless pressure through 11 phases before spilling the ball forward in contact three minutes from time. They refused to lie down, though. Chris Eaton scored a length-of-the-field try after a turnover in their own 22, Trent Boswell-Wakefield making a huge bust before feeding O'Connor who passed to Eaton to score in the right corner to silence the home crowd.

West stepped up to win the game with the final kick of the game, but he pulled his conversion attempt and Tasman and their fans celebrated their first title success.

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